Can't add account to mail on mac

Im running OS X El Capitan (Version 10.11.6) and I can't add additional accounts to my mail. Ive had the computer for over a year and all my accounts worked fine until about a 2 weeks ago, when my gmail accounts stopped receiving emails. My .mac e-mail was fine. So i deleted the accounts and then tried to re-add them thinking it would solve the problem however i cannot add them back.

I click on mail, add accounts, and then google. Which allows me to enter my e-mail and passwords just fine. But when it asks what apps i want to use with the account, i select mail and click done... and nothing happens. Then the Done button is grayed out but it hasn't been added.

any help?